Consider the following relationships among the members of a family of six persons A, B, C, D, E and F: The number of males equals that of females. A and E are sons of F. D is the mother of two, one boy and one girl. B is the son of A. There is only one married couple in the family at present. Which one of the following inferences can be drawn from the above?

Q 193 / 325

UPSC CSE Prelims 2017

Consider the following relationships among the members of a family of six persons A, B, C, D, E and F:

Which one of the following inferences can be drawn from the above?

Based on the provided relationships, a consistent family structure can be deduced:

From condition 1, a family of six with an equal number of males and females implies there are 3 males and 3 females.
Condition 2 states A and E are sons of F. This identifies A and E as males. F is a parent.
Condition 4 states B is the son of A. This identifies B as male.
With A, E, and B identified as males, the remaining three members (C, D, F) must be females.
Condition 5 specifies there is only one married couple.
If A is the husband of D, then A (male) and D (female) form the single married couple.
Condition 3 states D is the mother of two children, one boy and one girl. Since B is the son of A (condition 4) and A is married to D, B is the son of D. This fulfills the 'one boy' requirement for D's children.
To fulfill the 'one girl' requirement for D's children, C must be the daughter of A and D.
This arrangement is consistent with F being the mother of A and E (condition 2), where F is female and an older generation.
All conditions are satisfied: 3 males (A, B, E) and 3 females (C, D, F); A and E are sons of F; D is the mother of B (boy) and C (girl); B is the son of A; and A and D constitute the only married couple.
Therefore, the inference that A is the husband of D is correct.

Option 1: A, B and C are all females

As deduced from the conditions, A, B, and E are the three males in the family. C, D, and F are the three females. Therefore, the statement that A and B are females is incorrect.

Option 3: E and F are children of D

Condition 2 explicitly states that A and E are sons of F, making F the mother of E.
In the consistent family structure, D is the mother of B and C. Therefore, E and F are not children of D.

Option 4: D is the daughter of F

In the established family structure, F is the mother of A, and D is the wife of A. This relationship makes D the daughter-in-law of F, not her daughter.